Adaptive hierarchical supramolecular assemblies enabled by versatile boron-nitrogen Lewis pairs

Hierarchical self-assembly, inspired by nature, enables the construction of advanced superstructures with precise functions, offering insights into biological systems and artificial supramolecular assemblies. However, replicating such modularity and dynamic adaptability, particularly in crystalline forms, remains a significant challenge. Here, we employed a boroxine-based boron-nitrogen (B-N) coordination strategy to successfully construct a series of dynamic higher-order supramolecular Lego crystals (LCs) composed of two or more modules. The core of this design is the boroxine with multidentate and multi-angular coordination capabilities, which forms four brick-like secondary macromolecular modules by coordinating with luminescent N-donors via B-N interactions. Then these modules spontaneously self-assemble into luminescent LCs driven by cooperative intermolecular interactions. Notably, the higher-order LCs exhibit dynamic adaptability under stimulus-induced transformations, revealing both subtle structural changes and significant structural rearrangements through single-crystal-to-single-crystal (SCSC) conversions. This work introduces a robust hierarchical assembly strategy for constructing adaptable higher-order superstructural crystals and elucidates their responsive behaviors.